How can investors make a basis step-up election and exclude the gain on the sale of an interest in a Qualified Opportunity Fund after a QOZ loses its designation?

I understand the question to be asking whether an investor in a QOF can make an election to step up his/her basis in the QOF interest, if the opportunity zone (QOZ) in which the QOF has invested loses its designation as an opportunity zone. Under current law, an opportunity zone cannot lose its designation as such, so this would require an act of Congress. But let me provide an answer to the broader question of what happens if, after an investor has held an interest in a QOF for at least 10 years, the QOF loses its designation as a QOF? Can the investor still get the basis step-up to exclude his/her gain from a subsequent sale of the interest? The answer appears to be no-- the QOF's loss of its designation is an inclusion event and (subject to certain exceptions not applicable here) an inclusion event will preclude an investor from obtaining the basis step-up.